Hi! i want to ask is any chip which supports arduino, have atleast 10output pins and 5input pins, also each can be loaded 500mA or more?I want to make big project with led multiplexing, so my arduino one pin can load only 2 leds with 20mA current, but i need 25-30 leds in row to control. Also i think i could make 5bit combiter with bc547 transistors to use lesser pins. Please help me and leave advice

Now i understand! that 5bit computer which i mean is shift register... Whats why in led cubes sets transistors, its like shift registers.. Thanks you. One more question, do you know any shift register which can load atlest 500mA current or more?

if you need to source 500mA but insist on using 74HC595 shift registers, you can use the UDN2981AT. Its capable of sourcing your 500mA needed. Here is a video that covers the concepts extremely well. You may or may not be using a dot-matrix display, but this guy is using the 595 and 2981A Watch it, trust me, it'll help.

if you need to source 500mA but insist on using 74HC595 shift registers, you can use the UDN2981AT. Its capable of sourcing your 500mA needed.

500mA is the absolute maximum output current of the UDN2981. The recommended maximum is 350mA, and at that current the voltage drop is 1.8V typical, 2.0V maximum. If you drive just 3 of the 8 outputs simultaneously at 350mA, you will already be close to the device maximum power dissipation. So I advise against using the UDN2981 in this application.

Darlington arrays would be the best way to drive 500ma. What you could do is if you're concerned about overloading it, run half the led's on on darlington and half on another. I use them at near 400ma per pin, I haven't done it for a long period of time but it doesn't heat up at all in about 30 seconds, especially if they're off more than on.

The shiftPWM does not use multiplexing but it requires a lot of refreshing to maintain the brightness level of the LED.Do you need to control the brightness or are you going to just control on and off?Controlling brightness AND multiplexing a matrix is possible but even more CPU intensive.This is what you need to do for a multiplexed matrix.http://www.thebox.myzen.co.uk/Workshop/LED_Matrix.html